Regular physical activity (PA) has been shown to produce powerful positive effects on physical and mental health, as well as on longevity. As a result, Healthy People 2010, the health objectives for the nation issued by the U.S. Department of Health and Human Services, includes the promotion of PA in communities. As the number of effective interventions to increase PA proliferates, public health decisionmakers need to choose from the available strategies as ways of promoting PA in their communities while maximizing the effects of their scarce resources. This application proposes a cost-effectiveness analysis (CEA), a means of measuring the relative efficiency of alternatives, to help decisionmakers compare effective PA interventions. The study will use standard methods and a common metric to evaluate cost-effectiveness (CE) of all effective interventions recommended by the Task Force on Community Preventive Services, along with newer interventions published subsequently. Using a public health perspective, the individual CE ratio of these interventions will be calculated as cost per unit of metabolic equivalence (MET) hours gained. Published validated sources that translate different activities into METS will be applied to derive the standard effectiveness measure of MET hours gained from reported increases in PA. Because the costs of interventions are largely absent in the literature, the proposed study will estimate the costs by imputing dollar values from resource utilization required for each intervention and validating the estimates with study investigators and experts. The CEA results will be compared using CEA graphs and league tables for all interventions and for subsets of interventions that vary by type, target population, and settings. Extensive sensitivity analysis will be conducted to determine the impact of uncertainty on the CEA estimates. The results of the study will add important information to increase the comparability of PA interventions, which will, in turn, contribute to public health planners' decisionmaking in prioritizing and choosing among strategies to promote PA and, eventually, improve the health of the U.S. population. This application proposes an innovative, exploratory cost-effectiveness analysis to compare the relative efficiency of effective physical activity interventions. Using standard methods and a common metric to evaluate cost-effectiveness, the results of this study will add important information concerning the comparability of PA interventions, which will, in turn, help public health planners choose strategies to promote PA that are consistent with their priorities and will maximize the utility of the scarce resources available to promote PA. [unreadable] [unreadable] [unreadable]